1. Field of the Invention
This invention relates to an electrode array and a method of manufacturing an electrode array, and in particular, to a neurological electrode array microfabricated on a flexible substrate utilizing biocompatible materials.
2. Background of the Related Art
A current challenge in the neural sciences is to monitor and to simulate neural activity with high spatial resolution. This requires a large number of electrodes within a small area, and independent, low noise connections to data acquisition equipment. Current microfabrication techniques are capable of making these electrode arrays, but the potential use on human subjects greatly restricts the materials and physical characteristics that can be employed.
An object of the invention is to solve at least the above problems and/or disadvantages and to provide at least the advantages described hereinafter.
A further object of the invention is to provide a small biocompatible electrode array that can be utilized for electrophysiologic studies in humans and other mammals.
Another object of the invention is to create significantly high contact density than currently commercially available devices.
An electrode array according to a preferred embodiment of the invention includes a flexible substrate, and a plurality of electrodes disposed on the flexible substrate. The flexible substrate is preferably formed of polyimide. The contacts preferably have a diameter in the range of approximately 10 xcexcm to 1 mm, more preferably approximately 30 xcexcm to 200 xcexcm.
The electrode array is manufactured according to a preferred method of the invention by forming a plurality of electrodes on a flexible substrate by forming a metal line on the flexible substrate for each of the plurality of electrodes by depositing one or more metals using electron beam evaporation and then patterning the one or more metals. A contact is then formed on the flexible substrate for each of the plurality of electrodes using one of electroplating and embossing. An insulating film is formed on the flexible substrate except over the contacts and areas of the electrodes utilized for connections to an electrical device. Preferably, electroplating is utilized to form contacts less than approximately 100 xcexcm in diameter, and embossing is utilized to form contacts greater than approximately 100 xcexcm in diameter.
Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objects and advantages of the invention may be realized and attained as particularly pointed out in the appended claims.